Hi, Nyah. I'm not exactly sure what you're asking. I wouldn't pay too much attention to ads that say, "This hat provides x-amount of sun protection." Any hat will provide sun protection, some more than others, but that has to do with the amount of sunlight hitting one's face from an angle. Most Milans are a close weave and allow almost no light to hit the top of your head.

Hi Bob. I'm asking if milans have a tight enough weave to protect a bald head from dangerous sun rays. They typically do let pinpoints of light in through the weave so, I want to make sure that a hat like this would still provide enough protection for me. I have almost no melanin and therefore burn easily.

I have a UV tester, and I`ve tried this on various hats - its 0 on most straw hats, but I get your point - if any light can get through, UV could still get through on a strong day if you spend hours outside, just like a shirt won't protect you fully too. But the weaves on Milans are tighter than some of the looser weaves on cheaper straws, and even finer Montecristis may let in UV as they are so thin. Wear protection cream as well is my advice...

Milans as far as I know, have narrow brims so will only give limited protection. they are also light coloured so will reflect surrounding rays onto your face, however, it should prevent your noggin from gatting sunburned as long as you're not going to be spending hours under an afternoon summer sun.
If you do burn easily, prehaps you should consider a wider brimmed felt hat which would give you better all round UV protection.

Milans, like most other varieties of straw, are available in all widths of brim, stingy or wide, or in very broad ladies' style, even. They are available in nearly every color under the sun. I have a Black one, a gray one, dark brown, honey, natural, the list goes on. In ladies styles, the colors can get pretty wild. The older ones, though, were often made in a significantly more narrow (fine) gauge of braid which is no longer available. Another piece of minutiae... Milans are braided, not woven.

My Milan is an Optimo, natural-colored in a "teardrop" crease with about a 3" brim (I'm visiting my parents, so I don't have the hat handy to measure). I have worn it all day in bright sun and not seen any signs of redness on my large bald spot up top and it provides good protection to my face and ears, too.

Milans went through a period of high popularity in the 1950s-60s, so many vintage examples are stingies, but you can get Optimo or Art Fawcett to make a new one to your specs. Many other hatters (such as Peter Bros) have "milans" made with a different straw material, which are also available in a variety of crown and brim sizes.

To answer your specific question, I would think that your head would be getting enough protection from direct sun exposure with this hat, but you will also be wanting some air flow to keep cool and dry. The hat will only protect if you are actually wearing it. If you are too hot and sweaty to the point that you remove it, then it is no protection at all.

I am contemplating a couple of summer hat options and considering these same issues.

Everyone has different needs and lifestyles, but I find, here in the Tropics, that I don't really spend hours in the hot sun all that often: I'm usually walking from one source of shade to the other, unless I'm out on a boat or something like that. Also, even when I'm sitting relatively still, my head's moving enough so that whatever ray of sunlight might possibly get through my Milan wouldn't be enough to worry about.

My go-to brimmed Summer hat is one of several Akubra Capricorns, which are polystraw in a milano type weave, with a semi-see-through bit in the middle of the crown, all the way around, to vent it. I shave my head and have never had a problem with burning. Granted I hate the sun with a passion and try not to go outdoors at all if I can avoid it during July and August, but I do spend a lot of time in Beijing in hotter months, outside all day, and I've never had a problem with burning.

The weave of my milan is such that any pinholes would be too small to matter. When it's really hot, the hat often gets repositioned, as I stop to fan myslef, wip off sweat, pull it down to shade my eyes, etc. And since I am also moving around, the angle of the sun is constantly changing. So any pinprick of light sould be moving, too. The hat definitely provides adequate sun protection. It is my go-to summer hat, although I also have a beautiful panama optimo (from Optimo) and a shantung (from Shanghai's own Futoshi Hats).

The sun moves, as well as hat-wearers, so the angle of the sunlight constantly changes. Any decent straw hat, without large openings between the "straws" (natural or synthetic) should keep the top of your head safe from sunburn, although I would strongly recommend getting, at least, a 3" wide brim to keep from burning your neck, and particularly, your nose.

Warning.
So-called "milan" hats, these days, are usually made of synthetic material, although not necessarily, quite unlike originally when they were all natural fiber.
Make certain as to what you are getting before buying a "milan" hat.

Akubra makes nice hemp hats with leather sweatbands.
The Akubra Range, Reef, Plantation, and Byron hats all have 3" and wider brims.
The Range and Reef are both the same hat, except that the Range has a vented crown.
The Planter and Byron are both the same hat, except for the different hatbands and the Planter having a curled-edge brim. The Byron also has a snap-brim, which I discovered, accidentally, to my surprise.
All of the Akubra hemp hats can be easily re-shaped when they are wet. I have raised the crowns on all of my hemp Akubras, as well as giving my Range, Reef, and Balmoral hats upswept brim rears, and making the brim rear "snapable" in the case of the Balmoral.